Anyways, I'd call #1 an oval or rounded tip, #2 is definitely barrel tip, #3 an olive tip, #4 an acorn tip, and I guess #5 is a teardrop, yeah.

As for the stick sizes, those terms are so broken and misleading it befuddles me. Just look at the spread in 5A diameters you have from four major stick manufacturers: Vic's are .565, Pro-Mark's are .551, Vater's are .570, and Regal Tip's are .580. Pro-Mark's 5Bs are .590- they're actually closer to a Regal Tip 5A than that same RT5A is to Pro-Mark's 5A. None of the designations are standardized, every company has their own special ones that don't make any sense, and it's all a huge cluster. The only actual order seems to be a very general one of higher numbers indicating smaller diameter, which, like... what? Even bra sizes make more sense than this stuff.

Well, that's my rant. I guess if you want to just look up Zildjian's 'standard' models and base them off whatever's closest, that would be the best option.

I do remember reading now that stick sizes aren't standard... which is a shame.
I will get some Vic Firth 5's as I've read a fair amount of good things about them, although I will probably opt for a B rather than an A. Then again, I could pick up both and see what I think.

Vic Firth A's look like the Ziljian ???, which are slightly wider than the dipped sticks.